Need help bad!

[kerls03]

This is the deal I got my car finished about a week ago and it has been running pretty good except when I would start to slow down and put the car in neutral while I was moving the cars rpms would drop down to about 500 and then pop up to about 1000 and slowly come down to normal idle. About 3 days ago doing the exact same thing while slowing down taking the car out of gear it will just started dieing now for no reason. The tuner has had the car for last 2 days and has spoke with diablosport and a few other people and does not know what is happening with it.
here are my mods:
steig stage four port
accufab tb and ported plenum
60 lb injectors
mafia
jlt cai
metco 4 lb lower
billetflow 2.93 5 pc pulley set
kenny bell boost a pump
fluidyne heat exchanger
A bunch of gauges
magnaflow catted x and catback exhaust
sub frames
hr springs
triax shifter
denzo 24 plugs 2 stages colder
custom tune by ats and speedlab
Somebody please I need some advice. I just spent my savings and the car is not even driveable and nobody can tell me where to start
The throttle postioning senor is working.

 

[Tide612]

who is tuning the car?

 

[kerls03]

Bob Payton has modifed a tune from Rick ATS

 

[NewToFord]

Maybe a vacum leak. Mine was idling all over the place when I swaped my blower. Turns out I left the line off of the plenum. I put that back on and no more idle problems.

 

[ShelbyGuy]

i smell a dead intercooler pump

 

[kerls03]

I dont think my intercooler pump is out if you open the overflow it is still swirling and I have a intercooler temp gauge that never gets above 120 degrees. The weather is still real cool around here about 50 degrees.

 

[kerls03]

Could it be my plugs they are 2 stages colder and do not heat up as much as the ngk plugs.
I am so pissed off I want to just kill someone!